code: def test_tf_non_distributed(ray_start_4_cpus):
      """Make sure Ray Train works without TF MultiWorkerMirroredStrategy."""
  
      trainer = TensorflowTrainer(
          tf_quick_start_train_func,
          scaling_config=ScalingConfig(num_workers=1),
      )
      trainer.fit()
  
file_path: ray/python/ray/train/tests/test_examples.py
imports: import pytest
  from ray.air.constants import TRAINING_ITERATION
  from ray.train import ScalingConfig
  from ray.train.examples.horovod.horovod_example import train_func
  from ray.train.examples.pytorch.torch_fashion_mnist_example import train_func_per_worker
  from ray.train.examples.pytorch.torch_linear_example import train_func
  from ray.train.examples.pytorch.torch_quick_start import train_func
  from ray.train.examples.tf.tensorflow_mnist_example import train_func
  from ray.train.examples.tf.tensorflow_quick_start import train_func
  from ray.train.horovod.horovod_trainer import HorovodTrainer
  from ray.train.tensorflow.tensorflow_trainer import TensorflowTrainer
  from ray.train.torch.torch_trainer import TorchTrainer
label_desc: Use image node_id 2 for calling a global function with example usage: test_tf_non_distributed(ray_start_4_cpus) without return types